Signaling apparatus for telephone-stations.



m. 670,408. Patented Mar. I9, I901.

TLW. LUABIN G. SIGNALING APPARATUS FOB TELEPHONE STATIONS.

A mati'mi filed oct: 27, 1900.

(No Model.)

UNiTED STATES ATENT FFICE.

"THOMAS W. IJOARING, OFCLEVELAND, OH-IO, Assieuon T THECUYA HOGATELEPHONE COMPANY, 0 SAME PLACE.

'YSIGNALINGAAPPARATUS FOR TELEPHONE-STATIONS.

- SPECIFICATION forming part of Letters Patent No.- 670,408, dated March19, 1 901.

Application filed October 27,1900. Serial No. 84,689. (No model.)

To all whnin it may concern.-

Be it known that I, THOMAS W. LOARING, a citizen of the United States ofAmerica, and

a resident of the city of Cleveland, State of Ohio, haveinvented certainnew and useful Improvements in Signaling Appliances for SubscribersTelephone-Stations, of which the following is a specification.

Myinvention relates to improvements in signaling apparatus, and moreparticularly to im provemen ts in apparatus designed for sendingselective signals from the subscribers station of a telephone system,the objectof my invention being the provision of simplified and reliablecalling appliances for the sub scribers stations which are adapted toactuate responsive signal-receiving apparatus at the central oifice.

In a telephone system now in common use the selective calls or signalsare sent to thecentral oflice through the uiedium of magneto generatorsor induction-coils, which being associated with switch mechanism ofsomewhat complex character may be caused to transmit thesignaling-current to associated polarized relays disposed at the centraloffice, the said relays being adapted alternatively to be actuated bysuch currents. The mechanismhitherto employed for eifectingthetransmission of the requisite signaling-currents has necessitated theemployment of a large num-.

ber of switch-contacts, which in practice have been found frequently toget out of order, renderingthe subscribers station apparatus temporarilyinoperative. The switch-contacts, moreover, were found not infrequentlyto remain abnormally closed, thereby short-circuiting thesignaling-battery when the same was employed and renderingits renewalnecessary. The apparatus of my invention is materially simplified, thenumber of contact parts being greatly reduced, while difiicultiesdeveloped in the use of prior apparatus are entirely obviated.

I will describe myinvention in'its preferred embodiment as applied toatelephone callbox for the subscribers station, wherein a battery andinduction-coil in connection with the simplified switchwniechanism of myin'' vention are employed for transmitting the calling-currents fronrthesubscribersstation.

vice is employed for connecting the call ap- 6o pliance with theexternal circuit.

My said invention will be more readily understood by reference to theaccompanying drawings, forming a part of-this specification, inconnection with which I will set forth more particularly theconstruction and operation of the preferred embodiment of the invention.I Figure 1 of the drawings illustrates a subscribers telephone call-boxequipped in ac- 7o cordance with my invention, the call-box being shownopen and a small portion of the V apparatus being-broken away moreclearly to illustrate the construction. Fig. 2 is adiagram setting forththe circuit arrangement of the telephone call-box and indicating as wellthe signal-receiving apparatus at the central cfiice, and Fig. 3 is adetail view illustrating the reversing-switch mechanism.

The same characters of reference are employed in the several figures ofthe drawings to indicate the same part or parts.

- The telephone call-box of Fig. 1' is equipped with the usual localbattery b, which, in connection with the induction-coil d e, serves totransmit signaling-currents of high potential over the external circuitto the selective signaling-drops or polarized annunciators f, g,

h, and '11, disposed at the central office. These latter we may consideras being upon diflt'er-- 0 cut sections of a telephone-switchboard, asis required in a well-known system of telephony.

Associated with the induction-coil and battery are a number ofswitch-contacts a, c, m, an 1",adapted, respectively, to be operated 5by he corresponding push-buttons A, O, M, and R, mounted upon and havingplungers extending through the lid of the call-box. A polarizedcall-bellj is also placed upon. the I lid of the-box, by which signalsmay be rerd o ceived at thesubscribers station in the usual manner. jsupportgd upon the switch-hook k is seen the telephone-receiver Z, whichnormally maintains the calling-circuit closed within the .box. Y

In the upper portion of the call-box are seen two relays n and 0, whichnormally maintain one side of the line open, the latter relayalsocontrolling the circuit through hell j, which is normally closed.

engage an upwardly-extending insulatingstop q, carried upon spring 3.Springs 3 and t are normally maintained in contact; but they are causedto separate by the depression of the spring 0 or m, spring 3 beingcarried downward into engagement with stripp. At this time the extendedend of spring 0 or m is also brought into electrical contact with spring6. The depression of any of the springs a, c, m, or 'r through theagency of their respective push-buttons serves to close thebatterycircuit through theind notion-coil and actuate one or other ofthe relays. The relay n is energized by pressing button A or C and.

will establish connection with the left-hand. line a: of ,the externalcircuit appearing at binding-post it. This is accomplished by the actionof its L-shaped armature, which serves to engage contactspring n withits coacting spring 12. The relay-armature, it'will be seen, is looselyheld in position. bya screw at the end of the relay, upon which it is.free to rock under magnetic influence. Similarly relay 0 is energizedupon pressing button M or R, thus serving.- to establish connection withthe external grounded circuit between springs o' and 0" and also,asexplained, opening the normally closed bell-circuit between springs 0and o ,which otherwisewould shortcircuit the callingcurrent within thebox. The secondary windinge of theinduction-coil is connected betweenone side y of the line and the normally open relay'contacts n and 0.

Binding-post w is connected to ground and.

with relay contact-spring o.

.Quite obviously the circuits of the/telephone-call-box could be butimperfectly set forth upon Fig. 1, and accordingly Fig. 2 willbereferred to in order that I may make clear the arrangement and operationof said device. i

The annunciatorsf and g are connectedhetween the limbs :20 and y of theline and are adapted respectively'to be actuated by currents. ofnegative and positivepolar-ity. Similarly the annnnciato'rs handtare conthe induction--coil. ifrom the negative pole of'the battery by contheresulting signaling-current.

outtonsR or M are pushed, similar circuits nected in a branch 2 betweenline y and ground and may be alternatively operated by currents ofopposite polarity. These currents are generated inthesecondary e of theinduction-coil, which, however, it must be remembered, is normally uponopen circuit. Assuming'then that the annunciator f, which to carry outthe illustration we will say is disposed upon the A section of theswitchboard and is to be actuated, the subscriber will depress button Aand contact-spring a will be engaged with strip 19, closing the circuitof battery I) through the primary (1 of Circhit may be traced ductor 1to relay n, conductor 2, contacts a p, winding 01, from left to right,conductor 3, contacts 8 t, and conductor 4 to the positive pole of thebattery b.

The relay is excited I to attract its armaturenvhich closes the linecircuit'h: between contacts n and n. Upon releasing the button A thecircuit is ab-= ruptly broken and current of high potential isgenerated. in the secondary e and. trans mitted. toline a; 1;, thusserving'to throw the drop f and signal the operator at board A. Therelay is sufficiently sluggish in its action to permit the passage ofthe signaling-current before the line-circuit is opened. Pressing the 0button, it will be seen, serves to send a. current of opposite polarityover the same circuit to operate drop g. Thus the circuit may be tracedfrom. the battery through relay n, conductors 2 and 5, springs c and t,conductor 6, winding d, from right to left, strip p,spring s,an'd'conductor 4 to the battery. The-separation of springs s t, effectedin the manner described by actuating either of the contact-springs c orm, which are providedwith laterally-extending ends, serves to reversethe flow of the current in the wind-ingd with a corresponding reversalof When. the

are established through the relay 0, which is actuated to open. thegrounded bell-circuit and simultaneously close the circuit betweenconductor y and grounded binding-pnst w. it will. not be necessary, itis thought, to trace these circuits. step by step, since the polarizedannunciatorz' or it is operated in the same manner as is annunciatorf org.

The apparatus employed in my improved call-box, it will be seen, isgreatly simplified as compared with that hitherto devised. By thisconstruction I amable to effect themseessary circuit changes withone-third the number of. contact parts previously required and alsoinsure the requisite opening of the line and bell circuits.

That my invention is susceptible of other applicationsand ofmodifications not herein described willbe. apparent to those. skilled inart. I; have merely setforth the same in this specification in itspreferred form. r

I therefore claim, and desire tosecurefby Letters Batent, the following:7

1. In a call-box for subscribers telephonestations the combination witha source of electrical energy, of a plurality of switches m, r, s and tcontrolling said source of energy, whereby selective signals may betransmitted, and a relay 0 associated therewith controlling thecontinuity of the line-circuit, substantially as described.

2. In a call-box fol-subscribers telephonestations the combination withasource of electrical energy ofasignal-sendinginduction-coil associatedtherewith, a plurality of switches m, 1', s and t controlling saidsource of energy, whereby selective signals may be transmitted, and arelay 0 associated therewith controlling the continuity of theline-circuit, substantially as described.

3. The combination in apparatus of the class described, with asignal-generating coil, of a plurality of signal-sending switches, asource of electrical energy adapted to be connected by said switcheswith the said coil, and electromagnetic apparatus adapted to completethe line-circuit when the flow of current is established in the saidcoil, substantially as described.

4. In apparatus of the class described, the combination with a localbattery 12 of a signaling-switch r controlling the flow of current fromsaid battery, a signal-sending coil (Z, c, associated therewith, wherebyselective signals may be transmitted, a signal-receiving device j, and arelay 0 controlling the circuit continuity of the line and of thesignalreceiving device, substantially as described.

5. In a signaling appliance for subscribers telephone-stations thecombination with a plurality of signaling-switches for sending separateselective signals, of a reversing-switch associated with a portion ofsaid signal-sending switches and adapted to be actuated thereby,electromagnetic apparatus constituting a source of electrical energy forsending signals,

associated with said switches, and a relay device adapted to close thesignaling-circuit when the signal-sending switches are operated, wherebythe appropriate signal-receiving device connected with said appliancemay be actuated, substantially as described.

6. In a call-box for subscribers telephonestations the combination witha plurality of signal-sending switches as a, c, m and r, for sendingseparate selective signals, of a reversing-switch s, 15 associated withswitches c and m and adapted to be actuated thereby,

an induction-coil d e, a source of electrical energy and relays n and 0adapted alternatively to close separate signaling-circuits when thesignal-sending switches are operated, whereby the appropriatesignal-receiving device connected with the call-box may be operated,substantially as described.

7. In a signaling appliance for subscribers telephone-stations thecombination with a pl 11- rality of signal-sending switches for sendingseparate selective signals, of a reversingswitch associated with aportion of said signal-sending switches and adapted to be actuatedthereby, an induction-coil, a battery adapted to be connected therewith,a subscribers call-bell and a plurality of relays adapted alternativelyto close separate signaling circuits through the secondary winding ofthe induction-coil, and to remove the subscribers call-bell from circuitwhen the signal-sending switches are operated, whereby the appropriatesignal-receiving device connected with said signaling appliance may beactuated, substantially as described.

Signed at Cleveland, Ohio, this 24th day of October, 1900.

THOS. W. LOARING.

Witnesses:

ESTELLE HOFFMAN, ALBERT LYNN LAWRENCE.

